Field of the Invention
The present invention relates generally to vehicle coupling mechanism and more particularly to such mechanisms which cushion end thrust shocks between the vehicles and which have a pull-out and pivot feature for perfecting the alignment of the vehicle for coupling.
The art of interconnecting vehicles in a tractive mode is well established and typically an otherwise rigid coupling including a ball and socket arrangement is employed to permit the two vehicles to swivel angularly relative to one another in negotiating turns to the left or right as well as in negotiating abruptly encountered inclines. With such coupling schemes any jolt or shock experienced by one of the vehicles is immediately transmitted to the other by way of the coupling resulting in not only annoyance to the driver, but also, due to the relatively large masses of the vehicles, great strain on the coupling mechanism. Also in such conventional coupling schemes the towing vehicle must be rather precisely positioned relative to the towed vehicle in preparation for coupling the two together.
It has been recognized that a resilient coupling between the vehicles will distribute the effect of an abrupt shock over a longer time interval materially reducing the stress on the coupling mechanism. Prior art schemes have provided spring loading, cushioned bump stops at the ends of the coupling travel, multiple resilient bushings and other more complex resilient structures which experience shear during the cushioning action. An improvement on such resilient couplings is disclosed and claimed in our aforementioned application, the entire disclosure of which is specifically incorporated herein by reference.
It has also been recognized that the positioning of two vehicles preparatory to coupling may be expedited by the provision of a coupling mechanism which is movable within limits to compensate for imprecise initial alignment of the two vehicles. Such known schemes typically employ an at least two part hitch where one part may be moved relative to the other from a locked towing position by withdrawing a pin against spring tension from its locking position and moving the one part to perfect the hitch alignment. Such spring loaded pins passing through the two parts transmit the forces between those two parts. In addition to the drawbacks noted in the Applicant's aforementioned application, the prior art suffers from one or more defects, namely, the structures are complex, expensive to manufacture, the pin and holes are subject to wear, and some difficulty in aligning the spring loaded pin and corresponding holes may be experienced.